Is Cannabis a Potential Lung Cancer Treatment?

Medically Reviewed by Melinda Ratini, MS, DO on September 23, 2022
4 min read

Cannabis, better known to most folks as marijuana or pot, might have the potential to ease pain and other symptoms of lung cancer. But so far, there's no evidence it can work as a treatment for the disease.

Cannabis is a drug made from the dried leaves and buds of the Cannabis sativa plant. Some people smoke or eat marijuana for the "high" it gives, but it's also getting a look from experts for the chance that it can play a role in helping with certain medical conditions.

The active ingredients in cannabis are chemicals called cannabinoids. Tetrahydrocannabinol (THC) gives the "high" people get when they use marijuana. Cannabidiol (CBD) doesn't cause the same euphoric feeling, but it does relax the body.

Both THC and CBD may help relieve the side effects of cancer and its treatments.

CBD oil is an extract from the hemp plant -- a relative of cannabis -- mixed with oil. Unlike THC, CBD oil doesn't cause a high when you use it.

Cannabis and CBD products aren't FDA-approved to treat lung cancer. They shouldn't replace proven treatments like surgery, chemotherapy, radiation, and targeted therapy. If you want to try cannabis for medical purposes, ask your doctor whether it's safe for you.

Cannabis products come in a few different forms. You can:

  • Breathe them in as smoke or through a vaporizer
  • Eat or drink them
  • Apply them to your skin as a cream, patch, or spray

Your doctor can suggest a form based on your symptoms and which types of cannabis are legal in your state.

When you smoke marijuana, it goes to work within seconds, but the effects only last for about 1 to 3 hours. When you eat marijuana, it starts to work more slowly, but the effects can last for up to 8 hours.

Cannabis acts on your central nervous system and the immune system -- your body's defense against germs -- in ways that could help ease symptoms of lung cancer or its treatment, like these:

Pain. There's some evidence that marijuana eases pain, both from the cancer itself and from the nerve damage that treatments like chemotherapy can sometimes cause. It might help people who don't get enough relief from or may not tolerate  opioid pain medicines.

Nausea and vomiting. Medical marijuana may help relieve these symptoms, which are common chemotherapy side effects Dronabinol (Marinol , SYNDROS) is a synthetic drug that is approved to treat those side effects. 

These drugs may help when other anti-nausea drugs haven't worked. Your doctor can give you a prescription for them.

Weight loss. Dropping pounds is a common lung cancer symptom. You may lose weight because you don't have an appetite, or because your treatment causes nausea and vomiting.

Cancer can sometimes cause muscle loss, called cachexia. Marijuana may also help with this symptom.

Anxiety and sleep. Sleepiness is a side effect of cannabis. If you have cancer, cannabis may improve sleep and ease anxiety.

Studies done in cells and animals show that cannabis slows or stops the growth of certain cancer cells -- including lung cancer cells. But so far, there's no evidence that it works as a treatment for cancer in people.

There's also no evidence that CBD oil treats cancer or its symptoms, although it may ease anxiety, pain, and problems with sleep.

Research on marijuana as a cancer treatment has been slow because the federal government considers it an illegal drug. More studies are needed to learn how it might help with lung cancer and other types of cancer.

Although medical marijuana is safe overall, it can cause side effects like these:

Except for the two FDA-approved cannabis drugs, it's hard to know how much CBD or THC is in the products you buy. How strong the doses are varies with the type you take.

There have been reports of contaminants like lead, pesticides, or dextromethorphan (an ingredient in cough medicines) in cannabis and CBD products. A small number of people have gotten infections after using one of these. People with cancer are already at a higher risk for infections because their immune system is weaker than usual.

CBD oil might also affect how well your cancer drugs work. For these reasons, it's important to let your doctor know before you use CBD products, even if you can buy them over the counter.